Do you really want to change the Dim Standard or do you just want to be able to switch between showing imperial and metric (or any other set of two dimension)?   This first script will change the dimension standard to one set by the Constant ChangeTo.  Procedure ChangeDimStandard; {November 1, 2019} {© 2019 Patrick Stanford pat@coviana.com} {Licensed under the GNU Lesser General Public License} {Changes the dimension standard of a dimension to the string constant} {defined in Chan